Acoustic wave duplexer

Isolation characteristics between the reception acoustic wave filter chip and the transmission acoustic wave filter chip to provide a good acoustic wave duplexer. Comprising a reception surface acoustic wave filter chip 4 and a transmission surface acoustic wave filter chip 3 mounted on the substrate 2, the substrate 2 is a the first and second balanced terminals 7 and 8 and the common terminal 5 cage, balanced filter section at least one of the transmission surface acoustic wave filter chip 3 and the reception surface acoustic wave filter chip 4 has a first balanced signal terminal and the second balanced signal terminal as an input terminal or an output terminal , and the second is connected to the first wiring 15 that connects the balanced filter unit and the first balanced terminal 7, and the balanced filter unit and the second balanced terminal 8 anda second interconnection 16, the first and second interconnections 15 and 16, characterized in that intersect while being insulated between each other, the acoustic wave duplexer 1.